title: cGMP-dependent ABA-induced stomatal closure in the ABA-insensitive Arabidopsis mutant abi1-1.
abstract: • The drought hormone abscisic acid (ABA) is widely known to produce reductions in stomatal aperture in guard cells. The second messenger cyclic guanosine 3', 5'-monophosphate (cGMP) is thought to form part of the signalling pathway by which ABA induces stomatal closure. • We have examined the signalling events during cGMP-dependent ABA-induced stomatal closure in wild-type Arabidopsis plants and plants of the ABA-insensitive Arabidopsis mutant abi1-1. • We show that cGMP acts downstream of hydrogen peroxide (H(2) O(2) ) and nitric oxide (NO) in the signalling pathway by which ABA induces stomatal closure. H(2) O(2) - and NO-induced increases in the cytosolic free calcium concentration ([Ca(2+) ](cyt) ) were cGMP-dependent, positioning cGMP upstream of [Ca(2+) ](cyt) , and involved the action of the type 2C protein phosphatase ABI1. Increases in cGMP were mediated through the stimulation of guanylyl cyclase by H(2) O(2) and NO. We identify nucleoside diphosphate kinase as a new cGMP target protein in Arabidopsis. • This study positions cGMP downstream of ABA-induced changes in H(2) O(2) and NO, and upstream of increases in [Ca(2+) ](cyt) in the signalling pathway leading to stomatal closure.
authors.affiliation: National Academy of Sciences of Belarus, Institute of Biophysics and Cell Engineering, Minsk 220072, Academicheskaya 27, Belarus.
authors.forename: Lyudmila V
authors.initials: LV
authors.lastname: Dubovskaya
authors.affiliation: National Academy of Sciences of Belarus, Institute of Biophysics and Cell Engineering, Minsk 220072, Academicheskaya 27, Belarus.
authors.forename: Yulia S
authors.initials: YS
authors.lastname: Bakakina
authors.affiliation: National Academy of Sciences of Belarus, Institute of Biophysics and Cell Engineering, Minsk 220072, Academicheskaya 27, Belarus.
authors.forename: Ekaterina V
authors.initials: EV
authors.lastname: Kolesneva
authors.affiliation: National Academy of Sciences of Belarus, Institute of Biophysics and Cell Engineering, Minsk 220072, Academicheskaya 27, Belarus.
authors.forename: Dmitry L
authors.initials: DL
authors.lastname: Sodel
authors.affiliation: Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
authors.forename: Martin R
authors.initials: MR
authors.lastname: McAinsh
authors.affiliation: School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK.
authors.forename: Alistair M
authors.initials: AM
authors.lastname: Hetherington
authors.affiliation: National Academy of Sciences of Belarus, Institute of Biophysics and Cell Engineering, Minsk 220072, Academicheskaya 27, Belarus.
authors.forename: Igor D
authors.initials: ID
authors.lastname: Volotovski
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics*; D006152:Cyclic GMP / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000378:metabolism / Q000494:pharmacology; D009154:Mutation; D009569:Nitric Oxide / Q000494:pharmacology; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D054046:Plant Stomata / Q000187:drug effects*; D040901:Proteomics; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D009569:Nitric Oxide; D000040:Abscisic Acid; D006861:Hydrogen Peroxide; C087434:ABI1 protein, Arabidopsis; D010749:Phosphoprotein Phosphatases; D006152:Cyclic GMP